Weather-related crashes represent a significant concern in roadway safety. In 2001, more than 22 percent of vehicle crashes were weather-related. Over 16 percent of crash fatalities and more than 20 percent of crash injuries in passenger vehicles occurred in adverse weather and/or slick pavement. Most weather-related crashes occur when the pavement is wet and during rainfall. Toward the goal of reducing collisions while maintaining the integrity and sustainability of roadways, separate projects in both France and California in recent years have been developed to achieve the following objectives: Evaluating the effectiveness of surface pavement improvements, in terms of the reduction in collisions, thus allowing the selection of cost-effective countermeasures; understanding and modeling deterioration of skid resistance over time, and allowing timely and effective measurement of roadway surface status; exploring alternative collection method of skid resistance on roadway surface within the framework of cooperative infrastructure and vehicles; developing real-time system of monitoring roadway surface conditions and offering alerts to drivers.